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981.
市场经济中的安全工程专业   总被引:3,自引:0,他引:3  
基于市场经济背景和煤矿企业改革现状,阐明了矿山通风与安全工程专业改革的迫切性和发展的方向,探讨了改革方案。  相似文献   
982.
本文通过对国内外森林资源利用概况及我校林副产品加工专业的现状分析,阐述了该专业的发展前景。  相似文献   
983.
/ Historically, researchers applying the hedonic technique devoted little effort to testing alternative functional forms. This study used Box-Cox transformations on a hedonic model examining property value effects of a closed landfill to help select among alternative functional forms. Although this particular application found that a log-log functional form was appropriate, it appears that functional form may vary by problem and case study area selected. Benefit estimates generated using the hedonic technique may be substantial over- or underestimates if the incorrect functional form is chosen. Proximity to the landfill had no significant effect on property values.KEY WORDS: Hedonics; Functional form; Box-Cox; Landfills  相似文献   
984.
2 concentration, and global or regional temperature change. Such model projections are frequently used as the basis or justification for public policy decisions and legislation. A substantial need has therefore arisen to test and substantiate the veracity of mathematical model projections. Unfortunately, environmental models can never be truly validated because natural systems are never closed and model solutions are always nonunique. Partial model confirmation is possible, however, and entails demonstration of agreement between prediction and observation. Experimental ecosystem manipulation provides one of the best, and in many cases only, available basis for model confirmation. The use and potential misuse of data from experimental ecosystem manipulations for model testing is explored using examples drawn from the application of an acid–base chemistry model, MAGIC. As model projections provide an increasingly important basis for public policy decisions, and as both the scientific questions and the models become increasingly complex, it will become critical to provide data from a suite of well-designed ecosystem manipulation experiments in order to evaluate the quality and uncertainty of those model projections and the models upon which they are based.  相似文献   
985.
矿井安全评价中的几个问题的初步研究   总被引:1,自引:0,他引:1  
研究了矿井灾害系统危险评价中的几个关键问题,分析了煤矿灾害系统的结构特点,针对矿井灾害系统这样一个过程性本质模糊的灾害发生环境,提出了危险程度的模糊风险度量理论和基于此理论的定量表示方法,以及对不同灾害事故后果相关性计算方法。还论述了全矿与其各组成部分的危险程度之间的相互关系。  相似文献   
986.
/ The role of the public in resource management has undergone aprofound transformation over the past two decades. Public input has evolvedfrom the enthusiasm for the widespread emergence public participation in theearly 1970s, through the realization of the relative effectiveness and costsof lobbying activities in the 1980s, to the emergence of environmentaldispute resolution (EDR) as a promising new alternative for the 1990s.Throughout this changing dynamic, there has been little attention tofundamental conception. This paper addresses this lack of conceptualization.A model of convergence is proposed to explain this transformation and as thebasis for an improved understanding of effective interest representationstrategies. The defining characteristics of lobbying, public participation,and environmental dispute resolution in resources management are outlinedrelative to the publics they involve, interest activity, organization,influence on policy, participatory features, and empowerment. Knowledge ofthese aspects will further aid in the identification and implementation ofeffective strategies to interest representation on a context-specific basis.KEY WORDS: Interest representation; Public participation; Disputeresolution; Lobbying; Resource management  相似文献   
987.
Waste facility siting successes depend on many linked factors of facility design and impacts, site characteristics, and community beliefs and values. A facility siting framework is constructed to combine important elements and cause–effect linkages that affect the siting outcome. The framework consists of three main components: (1) core elements of facility design, effects, and community beliefs, attitude and response; (2) contributing factors of site and community characteristics, community beliefs and values that affect the interpretation of the facility and its effects; and (3) siting management interventions to manage the process and facility impacts. The framework is applied in an unsuccessful and a successful siting case to determine the key elements that contribute to siting outcome: (1) thorough need justification for the facility from the proponent's and the community's perspective; (2) careful facility design and prediction of the impacts and to select impact management compensation measures; (3) screening and selection of communities where the beliefs and values are compatible with the type of facility and its effects, (4) cooperatively selected impact reduction (i.e., prevention, control, and mitigation) measures followed by compensation and incentives; and (5) intensive process management to balance the community characteristics and values with the proponent's efforts to plan, design, assess and manage impacts, and ultimately, gain approval of the facility. The siting framework provides a comprehensive and robust structure of key factors that contribute to siting outcome and, therefore, provides the tool to identify, evaluate, and design siting interventions to enhance the chances of successful siting outcome.  相似文献   
988.
高等院校安全工程专业知识结构的探讨   总被引:5,自引:3,他引:2  
以马克思主义哲学为指导思想,安全科学技术体系为依据,阐述高等院校安全工程专业知识结构。  相似文献   
989.
本项研究是以雪貂(Ferret)和旱獭(Woodchuck)作为实验动物模型,由于这两种动物的某些器官特征在解剖学上和生理学上与人类有其相似之处,试图通过雪貂和旱獭体内生物合成亚硝胺,说明人类暴露于化学致场物亚硝胺的另外一个来源是生物体内合成。同时,用烷基化学致癌物二甲基亚硝胺对旱獭进行DNA烷基化的研究,发现由于被旱獭肝炎病毒(WHV,WoodchuckHepatitisVirus)感染的旱獭,不仅体内易于合成亚硝胺,而且其肝脏组织DNA烷基化的水平高于对照组。以DNA烷基化反应产生的烷化核酸碱基作为生物标志(Riomarkers),对于胃癌高发区人群尿中的烷化核酸碱基进行定量测定,并与低发区相对照,显示两者之间有差异性。本项研究为从动物实验外推到人群的设想提供了启示,还提出了以生物标志作为建立分子流行病学的依据。  相似文献   
990.
长江河口淡水资源利用与避咸蓄淡水库   总被引:2,自引:0,他引:2  
开发利用长江口的淡水资源 ,首先要研究河口水质的污染程度以及咸潮入侵的时空变化规律。长江河口水质除边滩存在局部污染外 ,主槽水质良好。长江口南支、南港、北港盐水来源主要有北支倒灌和外海盐水直接入侵两种形式 ,盐水入侵具有周日、半月、季节和年际变化规律 ,由于北支倒灌咸水团的影响 ,低盐度值往往出现在大潮期和涨憩附近。通过修建边滩水库 ,达到控制引水时间、避咸蓄淡的目的。最长连续超标天数的推算是确定水库库容的关键问题 ,采用数理统计、二维数值模拟、ARMAX模型 +Markov模型等方法推算 ,几种方法相互印证 ,计算结果基本上符合实际情况。“避咸潮取水 ,蓄淡水保质” ,这是宝钢干部、科技人员总结出来的长江河口引水经验。长江口取水工程由取水系统、调蓄水库和输水系统等三大部分组成。长江口避咸蓄淡水库的成功经验 ,对沿海潮汐河口的淡水资源开发利用具有示范作用。  相似文献   
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